Increased oxidative stress and altered substrate metabolism in obese children

Abstract

Pediatric obesity, a major risk factor for cardiovascular diseases and diabetes, has steadily increased in the last decades. Although excessive inflammation and oxidation are possible biochemical links between obesity and cardiovascular events in adults, little information is available in children. Furthermore, effects of gender and fitness on the interaction between dyslipidemia and oxidative or inflammatory stress in children are mostly unknown. Therefore, we measured systemic markers of oxidation (F2-isoprostanes, F2-IsoP, and antioxidants) and inflammation (interleukin-6, IL-6, and leukocyte counts) and metabolic variables in 113 peripubertal children (55 obese, Ob, age and gender-adjusted BMI%≥95th, 25F; 15 overweight, OW, BMI% 85th–95th, 8F; 43 normoweight, CL, 25F). Overall, when compared to CL, Ob displayed elevated F2-IsoP (99±7 vs. 75±4 pg/mL, p<0.005), IL-6 (2.2±0.2 vs. 1.5±0.3 pg/mL, p<0.005), elevated total WBC and neutrophils, and altered levels of total cholesterol, LDL-C, HDL-C, triglycerides, free fatty acids, glucose, and insulin (all p<0.005). This pattern was independent of gender and not caused by reduced fitness in Ob. Our data indicate that alterations in metabolic control and a concomitant increase in inflammation and oxidative stress occur early in life in obese children, likely exposing both genders to a similar degree of increased risk of future cardiovascular diseases.

Oxidative Stress in Obesity and Metabolic Syndrome in Children and Adolescents

“…Oxidative stress has been associated with obesity, hyperglycemia, hypertension and atherosclerosis [23,24,25,26]. Previous studies demonstrated that the earliest signs of CHD, such as coronary artery fatty streaks, are already present in childhood and rapidly increase during adolescence, particularly in those with elevated BMI [27,28].…”

Neuroendocrine Inflammatory Responses in Overweight/Obese Infants

“…This reaction leads to the formation of MDA, as is indicated by the elevated levels of TBARS in overweight or obese children [16,50]. However, the result of the biomarker of lipid peroxidation (TBARS) in this study was distinct from the evidence presented in the literature for school-aged children [16,22], and the reason for this difference is not completely understood. The lower SOD and CAT activities was similar to those of other studies, which demonstrated the presence of a low antioxidant defense in overweight and obese children [16].…”

“…Higher levels of leptin, resistin, soluble TNF receptors 1 (sTNFR1) and 2 (sTNFR2), monocyte chemoattractant protein-1 (MCP-1), regulated upon activation normal T-cell expressed and secreted (RANTES), interleukin-8 (IL-8), interferon-inducible protein 10 (IP-10), monokine induced by interferon-γ (MIG), ROS and cortisol, as well as lower levels of adiponectin, BDNF and antioxidant enzymes in school-age overweight or obese children can be observed [8,10,19,20,21,22,23,24,25]. Another study already demonstrated elevated C-reactive protein (CRP) levels, another inflammatory marker, in preschool obese children [26].…”

Comparison of inflammation and oxidative stress levels by the severity of obesity in prepubertal children

“…In addition, obese children displayed widespread alterations in their lipid profile, plasma glucose, and insulin compared to the control group. 11 Habib et al conducted a case-control study and compared obese children and adolescents aged 5-17 years with healthy control participants matched for age and gender. They also showed significant elevations in proinflammatory adipocytokines (tumour necrosis factor-a and IL-6) and an oxidative stress biomarker (MDA), as well as significant decreases in antioxidant defense mechanisms (glutathione, zinc levels, and superoxide dismutase activity) among obese individuals compared to the control group.…”